Chart.JS:在甜甜圈图表上永久显示自定义标签

<script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
<script src="https://cdn.jsdelivr.net/npm/chartjs-plugin-datalabels"></script>

<canvas id="myChart"></canvas>

var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
    type: 'doughnut',
    data: {
        labels: ['标签1', '标签2', '标签3'],
        datasets: [{
            data: [10, 20, 30],
            backgroundColor: ['#ff6384', '#36a2eb', '#ffce56']
        }]
    },
    options: {
        plugins: {
            datalabels: {
                color: '#fff',
                anchor: 'end',
                align: 'start',
                offset: 10,
                font: {
                    weight: 'bold'
                },
                formatter: function(value, context) {
                    return '自定义标签: ' + value;
                }
            }
        }
    }
});